000
FXUS61 KOKX 292031
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
431 PM EDT Tue Aug 29 2023
.SYNOPSIS...
A frontal system will impact the area tonight into Wednesday.
High pressure builds in from the Central Plains Thursday into
Friday and then remains over the area into early next week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Stationary front remains over the ocean tngt. This limits any
forcing, and with a lack of deep moisture, pops remain aob the
chance category thru at least midnight.
Heights begin to fall late tngt as the upr trof over the Great
Lakes approaches. Increasing chances for shwrs thru 12Z Wed as a
result. With the strongest forcing, some isold tstms were
included in the fcst.
The NBM with the usual local adjustments was used for temps.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Rainfall with the upr trof and associated cold front continues to
develop ewd thru Wed mrng. Again, isold tstms included with the
best forcing. The best dpva occurs across the nrn third of the
cwa nwd into the rest of New England per the 12Z modeling. As a
result, coverage and intensity across the srn 2/3 of the area
may be lessened. The 12Z NAM even keeps most of the cwa dry for
Wed. This was a bridge too far attm given the strength of the
upr trof, but the fcst has been limited to sct/chc pops
nonetheless.
After any rain exits late mrng into the early aftn, deep mixing
on nwly flow will produce highs generally in the 80s. The NBM
seemed reasonable based on this scenario and was followed.
Clearing skies and a nw breeze for Wed ngt. Stuck with the NBM
for temps due to the wind. If portions of the area are able to
decouple before sunrise Thu, lows there will verify at least a
few degrees colder.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
A rather quiescent long term period in store through the upcoming
weekend and into early next week, with mainly dry conditions and a
warming trend.
Global ensemble guidance is in good agreement with upper ridging
building and expanding over the region starting on Thursday. Height
rises commence on Thursday afternoon as the upper trough departs to
the northeast. The ridging and surface high pressure remain anchored
over the area through Sunday morning, with a warming trend expected
as the ridge axis passes east of the area by Saturday afternoon.
TC Idalia is forecast to pass well south of the area and off the
Carolina coast Thursday into early Friday. Other than some high
level cirrus from northern periphery of the system that may graze
the area, sunny and dry conditions are expected.
On Sunday, an upper trough and weak cold front then approaches from
the NW, but looks to wash out before reaching the area. High
pressure then builds back in for the start of next week continuing
the dry stretch.
The period will start off cooler than normal, with highs in the
upper 70s for Thursday before gradually warming back up into early
next week. Recent guidance is advertising some low 90s for highs
across the urban corridor on Monday (850mb temperatures near 21C)
under westerly flow, but cooler at the coasts with a more SW surface
flow component. NBM probabilities of >90F for Monday are in the 20-
40% range for northeastern NJ and NYC, up from yesterday.
Monitor https:/www.weather.gov/okx/tropical or http/www.nhc.noaa.gov
for the latest NHC forecasts on this tropical system and others.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
Generally MVFR or lower cigs through Wed AM, then VFR. Occasional
VFR possible into the evening before declining back to MVFR to IFR
this evening through Wed AM. There is potential for LIFR overnight
into the early morning hours.
Spotty light rain or drizzle possible for eastern terminals, KGON,
KISP into this evening, but most others remain dry for the moment.
Occasional showers become more likely everywhere overnight, tapering
from west to east Wednesday morning. Isolated thunder possible Wed
AM, but confidence remains too low to include in the TAF.
Winds remain easterly less than 10 kt into this evening, likely
becoming light and variable overnight, and then W/NW behind a cold
front by Wednesday afternoon. Speeds increase behind the front, 10
to 15 kt, with gusts 15 to 20 kt at times.
THE AFTERNOON KJFK, KLGA AND KEWR HAZE POTENTIAL FORECAST IS
YELLOW...WHICH IMPLIES SLANT RANGE VISIBILITY 4-6SM OUTSIDE OF CLOUD.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments possible with changing flight categories.
Timing of showers may be off by a couple of hours.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
Wednesday: VFR. Gusts up to 20 kt in the afternoon.
Thursday-Sunday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Swell from Franklin will keep seas at sca lvls on the ocean thru
Thu. Winds may approach 25kt at times Wed ngt behind a cold
front.
Seas are then expected to come down gradually Thursday night into
Friday night, with sub Small Craft Advisory conditions possible by
Friday morning. A 9 to 10 second S to SE swell is expected to linger
into early Saturday.
&&
.HYDROLOGY...
A band of heavier shwrs and tstms may develop late tngt into
early Wed for portions of the Lower Hudson Valley, particularly
across Orange county. Some localized minor flooding will be
possible in this band. Otherwise, no hydrologic concerns
expected through the weekend.
&&
.TIDES/COASTAL FLOODING...
-- Changed Discussion --
A High Risk for Rip Currents remains in effect for all but the
NYC beaches today as more energetic long period swells arrive
from Tropical Cyclone Franklin. The high rip risk continues for
all beaches on Wednesday as the surf is forecast to build to 6
to 7 ft, especially across eastern Long Island.
High surf and dangerous rip currents are likely to continue
into Thursday. A High Surf advisory may be needed for Wednesday
night into the first half of Thursday due to 5-7 ft southerly
swells with a period of 12-14s period. Swells will be nearly
perpendicular to the coast maximizing the surf height. Combined
with the high surf, the potential exists for areas of ocean
beach erosion/flooding and for scattered areas of dune erosion
during the times of high tide today/Wed.
Astronomical tides are on the rise due to a full moon Wednesday
night. A Coastal Flood Statement remains in effect for Southern
Fairfield, Staten Island and Brooklyn tonight, and statements
will likely be needed for the Wednesday and Thursday night high
tide cycles as well. A Coastal Flood Advisory is in effect for
Southern Queens and Southern Nassau tonight and advisories will
likely be needed for the Wednesday and Thursday night high tide
cycles.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 8 PM EDT this evening for NYZ080-
081-179.
Coastal Flood Advisory until 9 PM EDT this evening for NYZ178-
179.
NJ...None.
MARINE...Small Craft Advisory from 8 PM this evening to 6 AM EDT
Thursday for ANZ350-353-355.
&&
$$
SYNOPSIS...JMC/DBR
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...DBR
AVIATION...DR
MARINE...JMC/DBR
HYDROLOGY...JMC/DBR
TIDES/COASTAL FLOODING...